Denis Rychkov, a researcher at the 吃瓜官网 , together with fifth-year student Alexander Dubok, studied the relative stability of polymorphic modifications of pyrazinamide, an antimicrobial agent used to treat active tuberculosis during the initial stage of therapy. They assessed it alone and in combination with other agents, over a wide temperature range. The study was conducted to understand the stability of various forms of a substance in order to control its properties including solubility, dissolution rate, and bioavailability. This research took place within the framework of the study and prediction of the phenomenon of plastic deformation of molecular crystals (Russian Science Foundation grant no. 21-73-00094). in Crystals (Q2) journal.
Rychkov, Research Director, discussed their work,
The research was fully calculated to model the stability of pyrazinamide forms using quantum chemistry methods. It was conducted as part of a study of the mechanical properties of various polymorphic modifications of pyrazinamide. The logic of the study led us to modeling the stability of forms in a wide temperature range from 0K to the melting temperature.
The relevance of this research lies primarily in the broad study of the rare "bending" organic crystals phenomenon. The scientists found a system in which the composition is constant, and only the crystal structure affects the mechanical properties. Simulation of various properties in this type of system is a significant step forward in understanding the creation of "bending" crystals for various fields of science and technology: pharmaceuticals, high-energy materials, optoelectronics, nonlinear optics, etc. Currently, scientists are creating a scientific basis for the study and creation of these materials in the context of digital materials science.
Rychkov added,
This work is important not only because we resolved the issue of form stability (there was a variety of data in the literature), but we also proved that the bending 伪-form is more stable than the brittle 未-form at all temperatures up to the melting point. This is a surprising fact in many ways, since it turns out that the mechanically movable form is more stable in relation to thermodynamics. The idea of controlling mechanical properties is fascinating, by changing the temperature we can track how the transition from one form to another occurs.
